Apparatus and methods for interference detection and handling within unlicensed spectrum

ABSTRACT

Apparatus and methods for operating wireless devices using unlicensed frequency ranges with minimal transmission interruptions. In one embodiment, the apparatus and methods provide a mechanism for redirecting idle or inactive wireless devices to different frequencies in response to interference detection such as by 5 GHz-band radar. In one variant, the present disclosure provides methods and apparatus for allowing user device (UEs) using 5G NR-U spectrum to continue to operate upon radar detection by successfully switching the UEs to one or more frequencies that are free of radar operation. In one variant, a gNB controlling the UEs informs the AMF (access and mobility function) of a radar detection event, and the AMF initiates a paging towards idle UEs in order to allow the gNB to move the UEs to a frequency without radar operations. In another variant, a gNB switches its UEs to a different frequency without relying on the AMF.

PRIORITY

This application is a continuation of, and claims priority to, U.S.patent application Ser. No. 16/837,751 of the same title filed on Apr.1, 2020, and issuing as U.S. Pat. No. 11,317,296 on Apr. 26, 2022, whichclaims priority benefit of U.S. Provisional Patent Application Ser. No.62/909,548 entitled “APPARATUS AND METHODS FOR INTERFERENCE HANDLING INWIRELESS SYSTEMS” filed Oct. 2, 2019, each of which are incorporatedherein by reference in its entirety.

COPYRIGHT

A portion of the disclosure of this patent document contains materialthat is subject to copyright protection. The copyright owner has noobjection to the facsimile reproduction by anyone of the patent documentor the patent disclosure, as it appears in the Patent and TrademarkOffice patent files or records, but otherwise reserves all copyrightrights whatsoever.

BACKGROUND 1. Technological Field

The present disclosure relates generally to the field of wirelessdevices and networks thereof, and specifically in one exemplary aspectto interference detection and handling (e.g., for weather or otherradars) within unlicensed RF spectrum (e.g., that utilized by 3GPP 5GNR-U or MulteFire systems).

2. Description of Related Technology

5G New Radio (NR) and NG-RAN (Next Generation Radio Area Network)

NG-RAN or “NextGen RAN (Radio Area Network)” is part of the 3GPP “5G”next generation radio system. 3GPP is currently specifying Release 15NG-RAN, its components, and interactions among the involved nodesincluding so-called “gNBs” (next generation Node B's or eNBs). NG-RANwill provide high-bandwidth, low-latency wireless communication andefficiently utilize, depending on application, both licensed andunlicensed spectrum of the type described supra in a wide variety ofdeployment scenarios, including indoor “spot” use, urban “macro” (largecell) coverage, rural coverage, use in vehicles, and “smart” grids andstructures. NG-RAN will also integrate with 4G/4.5G systems andinfrastructure, and moreover new LTE entities are used (e.g., an“evolved” LTE eNB or “eLTE eNB” which supports connectivity to both theEPC (Evolved Packet Core) and the NR “NGC” (Next Generation Core).

In some aspects, Release 15 NG-RAN leverages some technology andfunctions of extant LTE/LTE-A technologies (colloquially referred to as4G or 4.5G), as bases for further functional development andcapabilities. However, numerous different and new architectural featuresare employed in 5G. Specifically, the NG-RAN (5G) System architecture isdesigned to support data connectivity and services offering with higherthroughput and lower latency than 4G or 4.5G. FIG. 1A shows the 5Garchitecture 100 as defined in 3GPP TS 23.501 (FIG. 4.2.3-1 thereof).

An existing 3GPP LTE/LTE-A/EPC (i.e., 4G or 4.5G system) cannot beupdated to support 5G; hence, 3GPP has also defined interworkingprocedures between such 4G/4.5G and 5G systems. FIG. 1B shows thearchitecture 101 for interworking between 5GS and EPC/E-UTRAN as definedin TS 23.501 (FIG. 4.3.1-1 thereof), specifically the non-roamingarchitecture for interworking between the 5GS and the EPC/E-UTRAN. Twodifferent RAN technologies are supported; i.e., E-UTRAN (4G/4.5G) 102,and 5G (NG-RAN) 104.

In LTE and 5G NR, for a given cell, the cognizant eNB/gNB broadcasts aPhysical Cell ID (PCI). The Physical Cell ID is the identification of acell at the physical layer (PHY). Typically, the UE 122 performsMeasurement Reporting, under network directive, based on detected PCIsfor a given EARFCN (E-UTRA Absolute Radio Frequency Channel Number) orfrequency/set of frequencies.

Unlicensed Spectrum

Various unlicensed spectrum is available worldwide for commercial use.Unlicensed technologies such as IEEE's 802.11 a/−n/ac/ax, 3GPP's LTELAA/eLAA/FeLAA, and 3GPP's NR-U (NR-Unlicensed) employ, for example, the5 GHz-band spectrum. In particular, in the United States, this spectrumis shared with Federal radar systems (e.g. TWDR). Other countries mayuse the 5 GHz and/or other unlicensed spectrum.

At the time of introduction of Wi-Fi (various versions of IEEE Std.802.11), IEEE had to devise mechanisms to ensure that Wi-Fi APs/STAs(access points/stations) either did not operate in frequenciesidentified as being used by radars or immediately vacated identifiedfrequencies in case of ongoing Wi-Fi transmissions. The resultingmechanism was a feature termed as “Dynamic Frequency Selection” (DFS).DFS is a mechanism that detects the presence of radar signals anddynamically guides a transmitter to switch to another channel whenever aparticular condition is met. Prior to the start of any transmission, anUnlicensed National Information Infrastructure (U-NII) device equippedwith DFS capability (e.g. Wi-Fi APs) must continually monitor the radioenvironment for radar's presence. If the U-NII device determines that aradar signal is present, it must either switch to another channel toavoid interference with the radar or go into “sleep mode” if no otherchannel is available.

3GPP is presently defining NR-Unlicensed (NR-U) to operate in a varietyof unlicensed spectrums, with the 5 GHz-band included. In order tomaintain regulatory compliance, NR-U therefore must provide a mechanismto allow continued operations of incumbent federal radar systems whileminimizing transmission interruption for NR-U.

It is noted that 3GPP LTE LAA did not require any specific mechanisms tosupport this functionality, due to the presence of a licensed carrier asits primary channel.

FCC's Regulatory Requirements for 5 GHz for Incumbent Radar Systems

DFS is a mechanism to allow (outdoor) unlicensed devices to operate in 5GHz frequency bands which have been allocated to radar systems withoutcausing interference within those radar systems. A DFS-enabled devicemonitors the channel it operates at and if radar signals detected, thedevice will vacate that channel and switch to an alternate channelautomatically. In addition, the channel in which radars are detectedwill not be used for a period of time.

The FCC issued a Notice of Proposed Rulemaking (NPRM FCC 03-110, 2003)requiring DFS and transmit power control to operate a wireless deviceoperating in, for example, the 5470-5725 MHz band in the United States.Test parameters for DFS are in Order FCC 06-96. There are also DFSrequirements for portions of the 5 GHz unlicensed spectrum in othercountries specified by respective regulatory agencies thereof. Hence,this issue of de-conflicting with Federal radars and other such systemsexists in other countries as well.

The FCC requirements for protecting radar channels are defined withrespect to the following terms:

-   -   Channel Availability Check Time: The time a system shall monitor        a channel for presence of radar prior to initiating a        communications link on that channel.    -   Interference Detection Threshold: The minimum signal level,        assuming a 0 dBi antenna, that can be detected by the system to        trigger the move to another channel.    -   Channel Move Time: The time for the system to clear the channel        and measured from the end of the radar burst to the end of the        signal transmission on the channel.    -   Channel Closing Transmission Time: The total transmission time        from the system during the channel move time.    -   Non-Occupancy Time: Time after radar is detected on a channel        that the channel may not be used.    -   Master Device: Device that has radar detection capabilities and        can control other devices in the network (e.g. an Access Point        would be considered a master device).    -   Client Device: Device that does not initiate communications on a        channel without authorization from a master device.

The above parameters may differ under various regulatory domains,however some typical values may be: CAC Channel availability time=60sec, Channel Move Time=10 sec, Channel Closing Transmission Time=1 sec,non-occupancy period=30 minutes.

According to regulatory requirements, a master device (e.g. an AP orbase station) performs the radar detection on behalf of all the deviceswithin that have associated with that master device. The implications ofthis include: a) if a client device (e.g. Wi-Fi station or UE) losesconnection to the master device, it shall not transmit anything to gainaccess to its master node or another master node in the same channel (oranother channel that requires DFS capability). The communicationsbetween master node and clients has to be sufficiently fast to meet therequirement that the device may only transmit for a total of 260 ms(Channel Closing Transmission Time) during a period of maximum 10 sec(Channel Move Time) after detection of a radar signal. A relatively slowconnection will leave the master node little time for coordinatingchannel changes with its clients.

DFS Operation in 5 GHz Spectrum and Related IEEE Std. 802.11 Procedures

With respect to 802.11 a/n/ac's DFS features, the specific 20 MHz-widewireless LAN channels and the equivalent frequencies are as follows(determined by the formula fc=5000 MHz+(5×channel number)):

-   -   UNII-2 channels are 52, 56, 60, 64 (center frequency 5260, 5280,        5300, 5320 MHz)    -   UNII-2 extended channels are 100, 104, 108, 112, 116, 120, 124,        128, 132, 136, 140 (center frequency at 5500, 5520, 5540, 5560,        5580, 5600, 5620, 5640, 5660, 5680, 5700 MHz)

In the Wi-Fi ecosystem, APs usually have the complexity to perform radardetection functions and in the event of detection of a radar signal, anAP instructs its associated stations to immediately move to anotherchannel. IEEE Std. 802.11h addresses this requirement by adding supportfor DFS and transmit power control on every DFS-required channel.

Once an AP detects radar on operating channel, a channel switchannouncement (CSA) element ID will be included in beacons and proberesponses to instruct the STA (here, a “slave”) to move to a newchannel. The exemplary CSA Element ID includes the following fields: (i)element ID, (ii) length, (iii) channel switch mode, (iv) new channelnumber, and (iv) channel switch count. The slave device should respondto the CSA element by checking its parameters. If the Channel switchmode is SET, the slave device stops transmissions to the AP. Conversely,if the Channel switch mode is CLEAR, the slave does not have anydependency on the AP for its operation.

Various Physical Channels for PCell/PSCell in 3 GPP NR-U

The channels subject to DFS for operation of LTE-LAA (Licensed AssistedAccess) and NR-U devices are channels within 46B and 46C. Table 1 showsthe sub-bands within Band 46. Corresponding channel(s) for NR areexpected to be defined as part of the ongoing NR-U WID.

TABLE 1 Uplink (UL) operating band Downlink (DL) operating band E-UTRABS receive BS transmit Operating UE transmit UE receive BandF_(UL)_low-F_(UL)_high F_(DL)_low-F_(DL)_high 46A 5150 MHz-5250 MHz 5150MHz-5250 MHz 46B 5250 MHz-5350 MHz 5250 MHz-5350 MHz 46C 5470 MHz-5725MHz 5470 MHz-5725 MHz 46D 5725 MHz-5925 MHz 5725 MHz-5925 MHz

As described above, for NR-U to operate in the 5 GHz band in the U.S.,it must support FCC's Title 47 Part 15 CFR. As noted, for IEEE's Wi-Fitechnology, DFS provides the necessary mechanism for this support.However, NR-U needs to have some mechanism as well, which is presentlyundefined in the standards (e.g., Rel.-15 and 16).

Because NR-U is a synchronous scheduled system, an NR-U UE generallycannot initiate transmissions without the knowledge of the gNB. An NR-UUE can operate in one of three RRC states, as shown in FIG. 1C:

-   -   1. RRC_CONNECTED    -   2. RRC_IDLE    -   3. RRC_INACTIVE

For UEs in the RRC_CONNECTED state, a handover mechanism exists whichmay be adapted to provide the necessary information for a UE in activetransmission/reception to shift the transmission/reception tofrequencies not used by any radar equipment. However, this mechanism isnot optimized for such functionality.

Moreover, no mechanism currently exists to inform UEs in RRC_IDLE orRRC_INACTIVE states of such radar detection events, and the expected ornecessary actions from the UEs.

Accordingly, improved apparatus and methods are needed to, inter alia,detect and manage interfering signals such as e.g., 5 GHz-band weatherradars, in wireless systems, including most notably idle or inactivewireless devices operating in unlicensed spectrums (e.g., in NR-U).

SUMMARY

The present disclosure addresses the foregoing needs by providing, interalia, methods and apparatus for operating wireless devices usingunlicensed spectrum during and subsequent to interference detectionevents. In one aspect, the disclosure provides methods and apparatus forswitching operating frequencies for devices being supported by a 5G gNBoperating in NR-U (New Radio-Unlicensed) during radar detection.

In one aspect, a method for managing detection of interference in afirst frequency channel being used in a wireless access network by awireless access node and one or more wireless user devices connected tothe wireless access network through the wireless access node. In oneembodiment, the method includes detecting wireless interference in thefirst frequency, selecting a second frequency that is free ofinterference, and switching the one or more wireless user devices fromthe first frequency to the second frequency. In one variant, the one ormore wireless user devices are initially in an idle or inactive mode.

In one implementation, the method includes: i) sending a paging signalto the one or more wireless user devices to cause the one or morewireless user devices to transition to connected/active mode; and thenii) sending a signal to the one or more wireless user devices to switchto the second frequency. In one specific configuration, the pagingsignal and transition to connected mode includes a 5G 3GPP compliantpaging procedure (i.e., using RRCSetup); the signal to switch to thesecond frequency is performed using 5G 3GPP compliant frequency changeprocedure (i.e., using an RRCRelease message); and the paging signal isinitiated by the access and mobility management function (AMF).

In another implementation, the method includes: sending a redirectmessage to the one or more wireless user devices from the wirelessaccess node (e.g., a gNB) without first “waking up” (switching toconnected/active mode) of the one or more wireless user devices. In oneimplementation, the redirect message is configured to signal the one ormore wireless user devices to switch their connection to the wirelessnetwork from the first frequency to the second frequency.

In another variant, the method includes monitoring a physical redirectchannel for the redirect message, the monitoring performed by the one ormore wireless user devices. In one variant, the one or more wirelessuser devices perform the monitoring while in the idle or inactive modes.In one implementation, the monitoring is performed periodically; e.g.,is performed at a predetermined monitoring frequency. In one particularconfiguration, the predetermined monitoring frequency depends on afrequency of monitoring of a paging channel (e.g., 3GPP defined paging).For example, in various approaches: i) the redirect channel monitoringis performed every time that a paging channel monitoring is performed(e.g., at time of paging monitoring, plus or minus t ms), ii) theredirect channel monitoring is performed every N times that the pagingchannel monitoring is performed, and/or iii) paging channel and redirectchannel monitoring are performed at different time domains, according toa predetermined schedule.

In one implementation, the monitoring frequency is provided to the oneor more wireless user devices by the wireless access node. Themonitoring frequency may depend on historical interference data. In oneconfiguration, the historical interference data includes the number oftimes that interference is detected in a particular channel frequencyband (first frequency band) within a time period. In anotherconfiguration, the historical data may include the frequency ofinterference signals during particular days of the week, days of themonth, times of day, types of day (weekend, weekday), etc. Thehistorical data may also include the frequency of interference signalswithin particular frequency bands (e.g., frequency bands 1 and 2 rarelyget radar interference, frequency band 3 is often busy on the weekends,etc.), such as via histogram or other data structure. For example, basedon a history of infrequent (or nonexistent) interference within a firstfrequency channel, the wireless access node may instruct the wirelessuser devices operating on the first frequency channel to monitor theredirect channel at a lower frequency or periodicity.

In one embodiment, the aforementioned wireless access node is a 5G gNB.In another embodiment, the wireless access node is a Wi-Fi AP (accesspoint). In one embodiment, the first frequency channel and the secondfrequency channel are at least in part located in an unlicensedfrequency spectrum. In one variant, the unlicensed frequency spectrum isthe NR-U spectrum, such as the unlicensed frequency spectrum is the 5GHz spectrum.

In one variant, the unlicensed frequency spectrum is a wireless spectrumused by Wi-Fi systems.

In one embodiment, the interference detection includes radar signaldetection in the first frequency channel, and the selecting a secondfrequency that is free of interference includes checking a list ofpre-selected frequency bands for interference. In one variant thereof,the pre-selected list frequency bands include all or some of the otherfrequency bands available to the wireless access node on the unlicensedspectrum. In another variant, the list of pre-selected frequency bandsis at least partially based on the historical interference data. In oneimplementation, the list of pre-selected frequency bands is tiered orordered, based on a prioritization structure, or based on historicalinterference data (e.g., frequency channels more likely to be currentlyfree are checked first).

In another aspect, a method of redirecting one or more wireless userdevices within a wireless access network from a first channel to asecond channel is disclosed. In one embodiment, the one or more wirelessuser devices are initially in idle or inactive state, and the first andsecond frequency channels are in an unlicensed frequency spectrum. Inone variant, the unlicensed frequency spectrum is part of the NR-Uspectrum; e.g., 5 GHz spectrum, and the wireless access network is atleast in part working in NR-U standalone deployment.

In another aspect, a method of operating a wireless user device in awireless network is disclosed. In one embodiment, the wireless userdevice is configured to perform channel frequency redirect in responseto channel interference detection. In one variant, the wireless userdevice is connected to a wireless access node of the wireless networkthrough a channel within an unlicensed frequency spectrum; e.g., 5 GHzNR-U spectrum. In one implementation, the channel interference detectionincludes detection of radar signal(s) in the frequency channel beingused by the wireless user device, the latter being an idle or inactivewireless user device. In one variant, the method further includesmonitoring a redirect channel for a redirect message.

In yet another aspect, a method of conserving power in one or morewireless user devices connected to a wireless network through a wirelessaccess node is disclosed. In one embodiment, the user devices areconfigured for performing channel frequency redirect in response to aninterference detection, and the method includes monitoring a physicalredirect channel for a frequency redirect message. In one variant, themonitoring is performed periodically, and the wireless user devices areotherwise idle or inactive so as to conserve power. The monitoring isperformed at e.g., a predetermined monitoring frequency provided to thewireless user devices by the wireless access node. In another variant,the monitoring frequency is calculated/established using historicalinterference data, in order to minimize user device power consumption(while e.g., still assuring that the user device discovers a redirectmessage within a certain time threshold). In one implementation, thehistorical interference data includes the number of interferencesdetected in a particular channel frequency band (first frequency band)within a time period.

In a further aspect, a method of operating a wireless access nodeconnected to one or more wireless user devices is disclosed. In oneembodiment, the wireless access node is connected to the one or morewireless user devices through a first frequency channel located in anunlicensed spectrum, and the wireless access node is a 3GPP NR gNBincluding an enhanced central unit (CUe) and/or at least one enhanceddistributed unit (DUe) connected to the central unit. In one variant,the method includes: performing interference (e.g., radar) detection inthe first frequency channel using the wireless access node; based ondetection of interference, selecting at least one second frequency; andsending instructions to the one or more wireless user devices from thewireless access node, the instructions configured to make the one ormore wireless user devices switch to the at least one second frequency.In one implementation, the at least one second frequency includes aplurality of different frequencies.

In one implementation, the foregoing interference/radar detection isperformed by a DUe of the gNB and the second frequency selection isperformed by the CUe. In another variant, the interference/radardetection and the second frequency selection is performed by a DUe ofthe gNB. In yet another variant, the interference/radar detection isperformed by a first DUe connected to the CUe and the second frequencyselection is performed by a second DUe connected to the CUe. In yet afurther variant, the radar detection and second frequency selection isat least in part performed by the UE.

In one embodiment, the foregoing method includes sending a RANconfiguration update from the gNB to the AMF (access and mobilitymanagement function) in the 5G Core (5GC), including information relatedto an interference detection event (e.g., radar detection). In oneimplementation, the information related to the interference detectionevent includes the first frequency and the second frequency.

In another embodiment, the wireless access node is configured to acceptone or more paging requests from an AMF, including a list of idle and/orinactive user devices currently using the first frequency.

In yet another embodiment, the wireless access node is configured tosend a paging message (provided by an AMF) to user devices (e.g., theidle/inactive user devices using the first frequency), and instruct theuser devices to switch to the second frequency.

In yet a further embodiment, the method includes using the wireless nodeto identify the idle and/or inactive user devices connected to thewireless access node through the first frequency; and sendinginstructions to the wireless user devices to switch to the secondfrequency. In one implementation, the sending the instructions includessending a redirect message, e.g., an RRC (radio resource control)redirect message, from the wireless access node to the idle/inactivewireless user devices.

In an additional aspect of the disclosure, a method of operating awireless access network including a wireless access node and one or morewireless user devices connected to the wireless access node through afrequency channel in an unlicensed spectrum is disclosed.

In a further aspect, a wireless user device connected to a wirelessnetwork through a wireless access node and adapted for performingchannel frequency change in response to interference detection isdisclosed. In one embodiment, the user device includes a 3GPP UEcompliant with Rel-15 and/or Rel-16. In one variant, the wireless userdevice, while in idle and/or inactive mode, is configured to detect apaging message from a wireless access node while the wireless userdevice is in idle or inactive mode (e.g., an NR-U UE operating inRRC_IDLE or RRC_INACTIVE states) and, in response to the paging message,to establish an active connection (e.g., switch to RRC_CONNECTED) withthe wireless access node using a first frequency. The wireless userdevice is further configured to, after establishing the activeconnection, detect a frequency change request (e.g., RRC Release) fromthe wireless access node and switch from the first frequency to a secondfrequency, based on the frequency change request.

In another embodiment, the wireless user device, while in idle and/orinactive mode, is configured to monitor a redirect channel (physicalchannel similar to the paging channel) for a redirect message and, inresponse to a redirect message, switch from a first frequency to asecond frequency, wherein the second frequency is provided in theredirect message. In one variant, the wireless user device is configuredto minimize power consumption during the monitoring of the redirectchannel. In one implementation, the minimization of power consumptionincludes monitoring the redirect channel based on historicalinterference data.

In yet another embodiment, the wireless user device is configured todetect interference on the first frequency. In one variant, the userdevice is configured to signal interference detection to its wirelessaccess node, and change channels based on instructions from the wirelessaccess node. In another variant, the user device is configured to selecta second frequency, change to the second frequency, and signal theinterference detection and the frequency change to the wireless accessnode.

In yet another aspect of the disclosure, a wireless network access nodeconfigured to provide network access to wireless user devices usingunlicensed spectrum is presented. In one embodiment, the wireless accessnode is configured to detect interference and to instruct one or more ofthe wireless user devices to switch from a first frequency to a secondfrequency, based on the detection of interference. In one embodiment,the wireless access node is a Wi-Fi access point.

In another embodiment the wireless access node comprises a 5G gNB node.In one variant, the gNB includes at least one distributed logical nodeunit (DU) connected to a central unit (CU). In one embodiment, theunlicensed spectrum is the 5 GHz spectrum. In one embodiment, theunlicensed spectrum is 5G NR-U spectrum.

In one implementation, the node comprises a computer program operativeto execute on a digital processor apparatus, and configured to, whenexecuted: (i) perform radar detection operation, (ii) upon detection ofradar in one of the frequencies on which the node currently operates,select one or more different frequencies (free from radar signals), and(iii) signal user devices to switch to the one or more differentfrequencies. In one variant, the computer program is configured toprovide radar detection and frequency information to a 5G AMF (AccessManagement Function).

In another aspect, an enhanced 5G NR network entity is disclosed. In oneembodiment, the network entity comprises an AMF.

In yet a further aspect, a computer readable apparatus is disclosed. Inone embodiment, the computer readable apparatus includes a digitalprocessor apparatus, a network interface, and computer readable storagemedium configured to store one or more computer programs. In onevariant, the one or more computer programs is configured to, whenexecuted: enable a wireless access node perform interference (e.g.,radar) detection, find interference in a first frequency, select asecond frequency without interference, and initiate an operationconfigured to switch one or more user devices from the first frequencyto the second frequency.

In another aspect, a computer readable apparatus for use on a wirelessuser device is disclosed. In one embodiment, the computer readableapparatus includes a digital processor apparatus, a network interface,and computer readable storage medium configured to store one or morecomputer programs. In one variant, the one or more computer programs isconfigured to, when executed: enable the wireless user device to, whilein idle or inactive mode, detect a frequency redirect message from awireless access node, and switch from a first frequency to a secondfrequency in response to the frequency redirect message. In anothervariant, the one or more computer programs is configured to, whenexecuted: enable the wireless user device to, while in idle or inactivemode, detect a paging message from a wireless access node, switch to anactive connection mode in response to the paging message, detect afrequency redirect message (while in the active connection mode), andswitch from a first frequency to a second frequency in response to thefrequency redirect message.

In another aspect, a network architecture for providing wireless networkaccess to one or more computerized user devices through a network accessnode through unlicensed spectrum is disclosed.

In still a further aspect, a method for managing radar operation in awireless network is disclosed. In one embodiment, the wireless networkincludes access points and user equipment devices operating in anunlicensed spectrum. In one implementation, the wireless networkincludes gNBs controlling UEs and operating in the 5G NR-U spectrum, andthe method includes: detecting a radar signal in a first frequency,wherein the first frequency is currently being used by the wirelessnetwork; selecting one or more second frequencies free of radaroperations; and switching/redirecting one or more UEs to operate on atleast one of the second frequencies.

In one variant, a network access point (e.g., a gNB) detects the radarsignal, selects the second frequencies, and initiates the switch to thesecond frequencies for the UEs. In another variant, an access point(gNB) detects the radar signal, selects the second frequencies, andcontacts a core network function (e.g., AMF), such that the core networkfunction initiates the switch to the second frequencies for the UEs. Inone embodiment, at least some of the UEs are in idle or inactive status,and the method includes transitioning the UEs into connected status.

In a further aspect, a network software architecture is disclosed. Inone embodiment, the architecture includes software elements or logicdisposed on: (i) a 5G network AMF; (ii) at least one gNB, and (iii) atleast one UE. In another embodiment, the architecture includes softwareelements or logic disposed on: (i) at least one gNB, and (ii) at leastone UE.

In another aspect, an improved system information configuration for usewith interference detection is disclosed. In one embodiment, the systeminformation broadcast by a gNB is enhanced for the purposes of DynamicFrequency Selection (DFS). For example, in one implementation, SystemInformation Block 1 (SIB1) in 3GPP Rel-16 NR, which currently conveysuac-BarringInfo that contains cell access control parameters fordifferent UE access categories, is enhanced with frequency redirectioninformation such that IDLE/INACTIVE/CONNECTED UEs can obtain thisinformation from reading SI, where the SI update is indicated viapaging.

These and other aspects shall become apparent when considered in lightof the disclosure provided herein.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1A is a functional block diagram of a prior art 5G systemarchitecture and the various components thereof.

FIG. 1B is a block diagram showing the extant architecture forinterworking between 5GS and EPC/E-UTRAN as defined in 3GPP TS 23.501(FIG. 4.3.1-1 thereof).

FIG. 1C is a graphical representation of prior art 5G NR UE RRC states.

FIG. 2 is a flow chart of one embodiment of a method of performinginterference detection by a 5G NR access node, according to the presentdisclosure.

FIG. 2A is a ladder/call flow diagram illustrating one exemplary exampleof performing interference detection which may be implemented in FIG. 2.

FIG. 2B is a simplified call flow diagram of a paging procedure for 5GSservices.

FIG. 2C is a ladder diagram illustrating one approach for performing ofinterference detection, in accordance with aspects of the presentdisclosure.

FIG. 2D is a ladder diagram illustrating another approach forperformance of interference detection, in accordance with aspects of thepresent disclosure.

FIG. 3 is a flow chart of another embodiment of a method of performinginterference detection via a wireless access node, according to thepresent disclosure.

FIG. 3A is a ladder diagram illustrating one approach for management ofinterference detection in a 5G NR network, in accordance with aspects ofthe present disclosure.

FIG. 3B is a ladder diagram illustrating another approach ofinterference detection in a 5G NR network, in accordance with aspects ofthe present disclosure.

FIG. 3C is a ladder diagram illustrating handling of interferencedetection in a wireless network, in accordance with aspects of thepresent disclosure.

FIG. 4A is a functional block diagram of a prior art gNB architectureincluding a central unit (CU) and multiple distributed units (DUs).

FIG. 4B is a functional block diagram of one exemplary embodiment of agNB architecture including a CU and multiple DUs, according to thepresent disclosure.

FIG. 5 is a functional block diagram illustrating a first exemplaryembodiment of an enhanced distributed unit (DUe) apparatus useful withvarious embodiments of the present disclosure.

FIG. 6 is a functional block diagram illustrating a first exemplaryembodiment of an enhanced central(ized) unit (CUe) apparatus useful withvarious embodiments of the present disclosure.

FIG. 7 is a functional block diagram illustrating a first exemplaryembodiment of an enhanced 3GPP AMF (Access Management Function) (AMFe)apparatus useful with various embodiments of the present disclosure.

FIG. 8 is a functional block diagram illustrating a first exemplaryembodiment of an enhanced User Equipment (UEe) apparatus useful withvarious embodiments of the present disclosure.

FIG. 9 is a block diagram showing one embodiment of aninternetworking-enabled architecture between enhanced 5GS with radardetection and EPC/E-UTRAN according to the disclosure.

FIGS. 2-9 © Copyright 2019 Charter Communications Operating, LLC. Allrights reserved.

DETAILED DESCRIPTION

Reference is now made to the drawings wherein like numerals refer tolike parts throughout.

As used herein, the term “application” (or “app”) refers generally andwithout limitation to a unit of executable software that implements acertain functionality or theme. The themes of applications vary broadlyacross any number of disciplines and functions (such as on-demandcontent management, e-commerce transactions, brokerage transactions,home entertainment, calculator etc.), and one application may have morethan one theme. The unit of executable software generally runs in apredetermined environment; for example, the unit could include adownloadable Java Xlet™ that runs within the JavaTV™ environment.

As used herein, the term “central unit” or “CU” refers withoutlimitation to a centralized logical node within a wireless networkinfrastructure. For example, a CU might be embodied as a 5G/NR gNBCentral Unit (gNB-CU), which is a logical node hosting RRC, SDAP andPDCP protocols of the gNB or RRC and PDCP protocols of the en-gNB thatcontrols the operation of one or more gNB-DUs, and which terminates theF1 interface connected with one or more DUs (e.g., gNB-DUs) definedbelow.

As used herein, the terms “client device” or “user device” or “UE”include, but are not limited to, set-top boxes (e.g., DSTBs), gateways,modems, personal computers (PCs), and minicomputers, whether desktop,laptop, or otherwise, and mobile devices such as handheld computers,PDAs, personal media devices (PMDs), tablets, “phablets”, smartphones,and vehicle infotainment systems or portions thereof.

As used herein, the term “computer program” or “software” is meant toinclude any sequence or human or machine cognizable steps which performa function. Such program may be rendered in virtually any programminglanguage or environment including, for example, C/C++, Fortran, COBOL,PASCAL, assembly language, markup languages (e.g., HTML, SGML, XML,VoXML), and the like, as well as object-oriented environments such asthe Common Object Request Broker Architecture (CORBA), Java™ (includingJ2ME, Java Beans, etc.) and the like.

As used herein, the term “distributed unit” or “DU” refers withoutlimitation to a distributed logical node within a wireless networkinfrastructure. For example, a DU might be embodied as a 5G/NR gNBDistributed Unit (gNB-DU), which is a logical node hosting RLC, MAC andPHY layers of the gNB or en-gNB, and its operation is partly controlledby gNB-CU (referenced above). One gNB-DU supports one or multiple cells,yet a given cell is supported by only one gNB-DU. The gNB-DU terminatesthe F1 interface connected with the gNB-CU.

As used herein, the term “DOCSIS” refers to any of the existing orplanned variants of the Data Over Cable Services InterfaceSpecification, including for example DOCSIS versions 1.0, 1.1, 2.0, 3.0,3.1 and 4.0.

As used herein, the term “headend” or “backend” refers generally to anetworked system controlled by an operator (e.g., an MSO) thatdistributes programming to MSO clientele using client devices, orprovides other services such as high-speed data delivery and backhaul.

As used herein, the terms “Internet” and “internet” are usedinterchangeably to refer to inter-networks including, withoutlimitation, the Internet. Other common examples include but are notlimited to: a network of external servers, “cloud” entities (such asmemory or storage not local to a device, storage generally accessible atany time via a network connection, and the like), service nodes, accesspoints, controller devices, client devices, etc.

As used herein, the term “LTE” refers to, without limitation and asapplicable, any of the variants or Releases of the Long-Term Evolutionwireless communication standard, including LTE-U (Long Term Evolution inunlicensed spectrum), LTE-LAA (Long Term Evolution, Licensed AssistedAccess), LTE-A (LTE Advanced), 4G LTE, WiMAX, VoLTE (Voice over LTE),and other wireless data standards.

As used herein, the term “memory” includes any type of integratedcircuit or other storage device adapted for storing digital dataincluding, without limitation, ROM, PROM, EEPROM, DRAM, SDRAM, DDR/2SDRAM, EDO/FPMS, RLDRAM, SRAM, “flash” memory (e.g., NAND/NOR), 3Dmemory, and PSRAM.

As used herein, the terms “microprocessor” and “processor” or “digitalprocessor” are meant generally to include all types of digitalprocessing devices including, without limitation, digital signalprocessors (DSPs), GPUs, reduced instruction set computers (RISC),general-purpose (CISC) processors, microprocessors, gate arrays (e.g.,FPGAs), PLDs, reconfigurable computer fabrics (RCFs), array processors,secure microprocessors, and application-specific integrated circuits(ASICs). Such digital processors may be contained on a single unitary ICdie, or distributed across multiple components.

As used herein, the terms “MSO” or “multiple systems operator” refer toa cable, satellite, or terrestrial network provider havinginfrastructure required to deliver services including programming anddata over those mediums.

As used herein, the terms “MNO” or “mobile network operator” refer to acellular, satellite phone, WMAN (e.g., 802.16), or other network serviceprovider having infrastructure required to deliver services includingwithout limitation voice and data over those mediums. The term “MNO” asused herein is further intended to include MVNOs, MNVAs, and MVNEs.

As used herein, the terms “network” and “bearer network” refer generallyto any type of telecommunications or data network including, withoutlimitation, hybrid fiber coax (HFC) networks, satellite networks, telconetworks, and data networks (including MANs, WANs, LANs, WLANs,internets, and intranets). Such networks or portions thereof may utilizeany one or more different topologies (e.g., ring, bus, star, loop,etc.), transmission media (e.g., wired/RF cable, RF wireless, millimeterwave, optical, etc.) and/or communications technologies or networkingprotocols (e.g., SONET, DOCSIS, IEEE Std. 802.3, ATM, X.25, Frame Relay,3GPP, 3GPP2, LTE/LTE-A/LTE-U/LTE-LAA, 5GNR, WAP, SIP, UDP, FTP,RTP/RTCP, H.323, etc.).

As used herein the terms “5G” and “New Radio (NR)” refer withoutlimitation to apparatus, methods or systems compliant with 3GPP Release15 (Rel-15), and any modifications, subsequent Releases (including e.g.,Rel-16 and Rel-17), or amendments or supplements thereto which aredirected to New Radio technology, whether licensed or unlicensed.

As used herein, the term “QAM” refers to modulation schemes used forsending signals over e.g., cable or other networks. Such modulationscheme might use any constellation level (e.g. QPSK, 16-QAM, 64-QAM,256-QAM, etc.) depending on details of a network. A QAM may also referto a physical channel modulated according to the schemes.

As used herein, the term “server” refers to any computerized component,system or entity regardless of form which is adapted to provide data,files, applications, content, or other services to one or more otherdevices or entities on a computer network.

As used herein, the term “storage” refers to without limitation computerhard drives, DVR device, memory, RAID devices or arrays, optical media(e.g., CD-ROMs, Laserdiscs, Blu-Ray, etc.), or any other devices ormedia capable of storing content or other information.

As used herein, the term “Wi-Fi” refers to, without limitation and asapplicable, any of the variants of IEEE Std. 802.11 or related standardsincluding 802.11 a/b/g/n/s/v/ac/ax, 802.11-2012/2013 or 802.11-2016, aswell as Wi-Fi Direct (including inter alia, the “Wi-Fi Peer-to-Peer(P2P) Specification”, incorporated herein by reference in its entirety).

Overview

In one exemplary aspect, the present disclosure provides improvedmethods and apparatus for operating wireless devices using unlicensedfrequency ranges with minimal transmission interruptions. In particular,the present disclosure provides inter alia, mechanisms for handling idleor inactive wireless devices during and subsequent to radar signaldetection.

In the exemplary context of a 5G NR-U network, User Equipment devices(UEs) in the RRC_IDLE mode are also in the EMM_IDLE mode at the NAS(non-access stratum) functional layer. In this mode, neither a NASconnection nor an RRC connection exists for such UEs. Such UEs can betransitioned to the EMM_CONNECTED state via a NAS-level pagingoperation. Such a page can be initiated by the AMF. However, the AMF isa Core Network element which has no radio transmit/receive equipment,and further does not perform radar detection.

Hence, in one embodiment, the present disclosure provides methods andapparatus for allowing such UE(s) using NR-U spectrum (an in eitherRRC_IDLE or RRC_INACTIVE state) to continue to operate after radardetection by successfully switching the UE(s) to one or more different(radar-free or unencumbered) frequencies. In one variant, a gNBcontrolling the UE(s) informs the AMF to initiate a paging operationtowards the UE(s) to move the UE(s) to a frequency without radaroperations, based on the gNB or its proxy detecting or becoming aware ofincipient radar operations.

In another variant, a gNB moves its UE(s) to a different frequencywithout relying on the AMF (i.e., it locally detects and initiates“paging” of the affected UE(s) in order to invoke the move.

In other variants, enhancements are provided to enable notification andmovement of even RRC_CONNECTED UEs (e.g. via modification of a SIB tore-direct connected mode UEs), whether in addition to the aforementionedinactive/idle state functionality.

In yet other variants, one or more UE are relied upon for at least aportion of the radar operation detection; data relating to the detectionis passed from the detecting UE(s) to the gNB, which then invokes eitherthe network-based (i.e., AMF involved) or local (non-AMF involved)procedures discussed above. In one approach, portions of radar operationdetection performed by a UE may be part of a co-located technologywithin the device wherein the UE resides; e.g. a Wi-Fi device (e.g.Wi-Fi Access Point or Wi-Fi STA).

Furthermore, embodiments are presented to permit gNBs to indicatefrequency changes to other gNBs that may be relying on transmissionsfrom the first gNB for various purposes, such as integrated access andbackhaul (IAB) or RAN-based synchronization. In one variant, the othergNBs are signaled directly from the affected gNB. In another variant,the other gNBs are signaled indirectly, such as via the AMF or otherproxy entities of the affected gNB.

DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS

Exemplary embodiments of the apparatus and methods of the presentdisclosure are now described in detail. While these exemplaryembodiments are described in the context of the previously mentionedwireless access nodes (e.g., gNBs) associated with or supported at leastin part by a managed network of a service provider (e.g., MSO and/or MNOnetworks), other types of radio access technologies (“RATs”) and/orother types of networks and architectures that are configured to deliverdigital data (e.g., text, images, games, software applications, videoand/or audio) may be used consistent with the present disclosure. Suchother networks or architectures may be broadband, narrowband, orotherwise, the following therefore being merely exemplary in nature.

For example, in one alternative application, the methods and apparatusdisclosed herein are used in conjunction with a 4G core used withunlicensed 5G (e.g., 5 GHz-band) infrastructure and spectrum, such as ina MulteFire network.

In another alternative application, the methods and apparatus disclosedherein are used in conjunction with 3GPP infrastructure used with CBRSspectrum (e.g., for incumbent detection such as military radar orcommunications before a SAS or other entity notifies of a GAA/PALspectrum withdrawal). See e.g., co-owned and co-pending U.S. patentapplication Ser. No. 16/791,352 filed Feb. 14, 2020 and entitled“APPARATUS AND METHODS FOR GENERATING AND DISTRIBUTING POLICY INWIRELESS NETWORKS”, which is incorporated herein by reference in itsentirety, for exemplary infrastructure and policy regardingquasi-licensed and unlicensed spectrum allocation which may be usedconsistent with the present disclosure.

Other features and advantages of the present disclosure will immediatelybe recognized by persons of ordinary skill in the art with reference tothe attached drawings and detailed description of exemplary embodimentsas given below.

Access Node-Assisted CN-Paging Enhancements and Methods

Referring now to FIGS. 2 and 2A-2D, exemplary embodiments of methods ofusing one or more access nodes (e.g., gNBs) and a network entity (e.g.,5G AMF) to manage interference (e.g., radar) found in a frequencychannel being used by at least one idle or inactive user or clientdevice (e.g., UE) registered with the access nodes are described.

As shown in FIG. 2 , one embodiment of the generalized method 200includes first detecting interference or a prospective interferer perstep 202. As used herein, the term “detect” may be active or passive;i.e., it may be an actual detection of electromagnetic emissions frome.g., weather radar, or it may be data or messaging indicating that theinterferer is present/operational or about to become so. In one variant,the access node (gNB or a proxy detection device thereof) performs thedetection.

Per step 203, the access node (e.g., gNB or a proxy node thereof)selects a new frequency band or group of frequencies (e.g., carriers orbands of carriers) which are putatively free of interference. This mayagain be active or passive in nature; i.e., via actual monitoring of thecarrier(s), or via data/massaging indicating that there are nointerferers currently operational or planned for at least a prescribedperiod of time.

Per step 204, the gNB or its proxy informs the network entity (e.g.,AMF) of the “detection” event and the selected new carrier(s).

Per step 206, the network entity (e.g., AMF) locates or identifies allidle or inactive user or client devices (UEs) associated with thereporting gNB(s).

Per step 208, the AMF initiates paging toward the affected/identifiedUEs to alert them to the incipient channel change.

Per step 210, in response to the paging, the identified UEs eachtransition to an active/connected (RRC_CONNECTED) state, and per step212, the UEs are all redirected by the cognizant gNB of the redirectionto the new carrier(s).

FIG. 2A illustrates an exemplary call flow/ladder diagram of a method ofdetecting interference (e.g., radar) and transitioning e.g., idle UEsfrom a first frequency to a second frequency, based on the detection. Inthe call flow Operation 0, the UE registers with the network (AMF) via agNB following normal 5G Registration procedures (per 3GPP TS 23.501 andTS 23.502). Upon completion of registration, at some point the UEtransitions to RRC_IDLE and EMM_IDLE (per 3GPP TS 38.300 and TS 38.311).

In call flow Operation 1, the gNB, assumed to be operating in a firstfrequency (i.e., frequency “X”), detects incumbent radar operations.Upon such detection, the gNB picks a frequency where no radar operationsare present e.g. frequency “Y.” The gNB starts broadcasting NR serviceparameters on frequency Y with the same Physical Cell ID (PCI) as thatof frequency X. This process corresponds to steps 202-203 of FIG. 2 ,wherein the gNB detects interference (e.g., radar) in a currentfrequency being used by at least one of its UEs and selects one or morenew frequencies for the UEs to switch to.

As shown in Operation 2 of FIG. 2A, the gNB initiates a N2-AP RANCONFIGURATION UPDATE message by setting RadarDetected to true, and foreach affected frequency CurrentOperatingFreq (X), it includes thecorresponding new frequency to which redirection of UEs is to occurNewOperatingFreq (Y) in AffectedCarriers. Note that the RANCONFIGURATION UPDATE message is sent by the NG-RAN node to transferupdated application layer information for an NG-C interface instance(with direction: NG-RAN node AMF). This operation corresponds to step204 in FIG. 2 , where the gNB informs the AMF function within the 5GCore of the interference detection event, along with the new frequency(Y) it wants to use (e.g., move UEs to).

In transmission (Operation 3) of FIG. 2A, the AMF acknowledgessuccessful receipt of the RAN CONFIGURATION UPDATE with a RANCONFIGURATION UPDATE ACKNOWLEDGE message per 3GPP TS 38.413.

In Operation 4 of FIG. 2A, when the AMF receives RadarDetected=True froma gNB, it looks up all EMM_IDLE UEs in its context. For those UEsassociated with this gNB, the AMF initiates CN-paging, but does notstart the paging supervisory timer (T3513). In call flow Operation 5,the AMF sends an N2-AP PAGING message to the gNB with the identity ofthe UE to be paged. In call flow Operations 6-9, normal paging behaviorper 3GPP TS 38.300 and TS 38.311 applies.

The AMF looks up the context of all EMM_IDLE UEs associated with thatgNB, and initiates paging towards those UE. In one variant, a normalpaging procedure follows. In one implementation, this may be implementedin Operations 6-9 of FIG. 2A.

The paged UEs transitions to RRC_CONNECTED status, and in Operation 10of FIG. 2A, the gNB redirects those UEs to the new carrier frequency(Y). In call flow transmission (Operation 11), the gNB sends RRCReleasewith carrierFreq in redirectCarrierInfo to Y to the affected UE(s).

The following Tables 2-5 illustrate various exemplary 3GPP-based IEs(information elements) and associated protocols useful with the methodsand apparatus described in the present disclosure.

TABLE 2 IE type and Semantics Assigned IE/Group Name Presence Rangereference description Criticality Criticality Message Type M 9.3.1.1 YESreject RAN Node Name O PrintableString YES ignore (SIZE(1 . . . 150, . .. )) Supported TA List 0 . . . 1 Supported TAs YES reject in the NG-RANnode. >Supported TA Item 1 . . . <maxnoofTACs> — >>TAC M 9.3.3.10Broadcast TAC — >>Broadcast PLMN 1 — List >>>Broadcast 1 . . .<maxnoofBPLMNs> — PLMN Item >>>>PLMN Identity M 9.3.3.5 Broadcast —PLMN >>>>TAI Slice M Slice Support Supported S- — Support List ListNSSAIs per 9.3.1.17 TA. Default Paging DRX O Paging DRX YES ignore9.3.1.90 Global RAN Node ID O 9.3.1.5 YES ignore RadarDetected O 9.3.1.XWhether gNB YES ignore detected radar activity on a certain frequencyAffected Carriers List O 1 YES ignore >AffectedCarriers List 0 . . .<maxnoofFreqPairs> — item >>CurrentOperatingFreq M NR ARFCN Current —9.3.1.Y operating freq (NR ARFCN) >>NewOperatingFreq M NR ARFCN Freq (NR— 9.3.1.Y ARFCN) to which UEs need to be redirected

TABLE 3 Range bound Explanation maxnoofTACs Maximum no. of TACs. Valueis 256. maxnoofBPLMNs Maximum no. of Broadcast PLMNs. Value is 12.maxnoofFreqPairs Maximum no. of Frequency (NR ARFCN) Pairs affected byradar detection. Value is 32.

The RadarDetected IE (Table 4 below) indicates that the gNB has detectedradar activity on its current operating frequency.

TABLE 4 IE type and Semantics IE/Group Name Presence Range referencedescription RadarDetected M ENUMERATED (true, . . . )

The NR ARFCN IE (Table 5 below) generally corresponds to maxNARFCN fromTS 38.331.

TABLE 5 IE type and Semantics IE/Group Name Presence Range referencedescription NR ARFCN M INTEGER (0 . . . 3279165)Paging for 5GS Services

In one exemplary embodiment of the present disclosure, the network(e.g., the AMF in the exemplary 5G context) initiates a paging procedurefor 5GS services when NAS signalling messages or user data ispending/waiting to be sent to the UE in 5GMM-IDLE mode over 3GPP access(see the example shown in FIG. 2B).

To initiate the procedure, the 5GMM (5G Mobility Management) entity inthe AMF requests the lower layer to start paging, and starts a timer(T3513). If the procedure is initiated due to receiving a RANconfiguration update from a gNB indicating that radar activity wasdetected, then the AMF requests the lower layer to start paging, but notstart the timer T3513.

If downlink signalling or user data is pending to be sent over non-3GPPaccess, the 5GMM entity in the AMF indicates to the lower layer that thepaging is associated to non-3GPP access.

Upon reception of a paging indication, the UE stops the timer (T3346),if the timer is currently running, and initiates: (i) a service requestprocedure over the 3GPP access to respond to the paging as specified insubclauses 5.6.1; or (ii) a registration procedure for mobility andperiodic registration update over the 3GPP access to respond to thepaging as specified in subclauses 5.5.1.3.

The network (e.g., AMF) stops its timer T3513 for the paging procedurewhen an integrity-protected response is received from the UE and issuccessfully integrity checked by the network. If the response receivedis not integrity protected, or the integrity check is unsuccessful, theAMF timer T3513 for the paging procedure is kept running. Upon expiry ofthe timer T3513, the network may reinitiate paging.

If the network, while waiting for a response to the paging sent withoutpaging priority, receives downlink signalling or downlink dataassociated with priority user-plane resources for one or more ProtocolData Unit (PDU) sessions, the network stops the timer T3513, and theninitiates the paging procedure with paging priority.

FIG. 2C is a ladder diagram illustrating one approach for performing ofinterference detection (utilizing the AMF, but with an enhanced DU(DUe), as discussed below, performing all the requisite managementlogic), in accordance with one embodiment of the present disclosure. Inone aspect of the disclosure, the method 200 of FIG. 2 may beimplemented as shown in the ladder diagram of FIG. 2C. In a gNBarchitecture that includes e.g., an enhanced CU (CUe) and at least oneDUe connected to the CUe, as will be later described with respect toFIG. 4B, one of the DUe's may locally perform all the interferencedetection and frequency selection of the method 200.

In one embodiment, during steps 202-203 of the method 200, a local DUe(or its proxy) performs radar detection, detects radar operation at afirst frequency X and, upon such detection, selects another frequencythat does not have radar interference (second frequency Y). In onevariant, the first frequency is located in an unlicensed spectrum, andselecting the second frequency includes identifying a plurality ofalternate frequencies in real time (e.g., other frequencies within theunlicensed spectrum) and identifying/selecting an unoccupied frequencyfrom the plurality of alternate frequencies. In another variant,selecting the second frequency includes obtaining a predetermined listof alternate frequencies and identifying/selecting an unoccupiedfrequency from the predetermined list of alternate frequencies.

In one embodiment, as shown in FIG. 2C, the DUe initiates the radardetection operation (e.g., periodically, or according to anothercriterion such as being triggered by an event). In another embodiment,as shown below with respect to FIG. 2D, the DUe may perform the radardetection operation in response to a signal/instruction from its CUe.The radar detection and second frequency selection may be performed forinstance using local detection management logic (DML) of the DUe. TheDUe communicates a radar detected message (including an indication ofboth frequencies X and Y) to its CUe, e.g., as a RAN CONFIGURATIONUPDATE. In step 204, the CUe transmits the radar detected message ontothe AMFe function within the 5G network.

The AMFe transmits an acknowledgement of the radar detected message tothe CUe and in one variant of step 206, identifies all the currentlyidle/inactive UEs being serviced by the DUe using frequency X.

In step 208 of the method 200 (as implemented in the exemplaryembodiment of FIG. 2C), the AMFe transmits a paging request (with theidentified user device) to the CUe in order to transition the identifieduser devices to an active/connected state. As shown in FIG. 2C, afterthe CUe transmits the initial paging message to the UEs via the DUe,steps 210-212 are performed by the DUe. In one embodiment, after theinitial paging request, the DUe independently handles the transition ofthe UEs from idle to connected and, once the transition is complete,instructs the UEs to switch from frequency X to frequency Y.

FIG. 2D is a ladder diagram illustrating another approach for performingof interference detection (utilizing the AMF, but with an enhanced CU(CUe) and an enhanced DU (DUe), as discussed below, performing all therequisite management logic), in accordance with another embodiment ofthe present disclosure. In the embodiment of FIG. 2D, different portionsof the requisite interference detection management logic of a gNB may behandled by different portions of the gNB (the CUe and the DUe's). Forexample, the CUe initiates an interference detection operation bysending an instruction to the DUe to perform interference detection.Similar to the embodiment of FIG. 2C, the DUe performs radar detectionand, in response to a detection of radar operation on frequency X,identifies one or more alternate frequencies. In one embodiment, the DUemay identify frequencies within the unlicensed spectrum that are free ofinterference, and transmit a list of the identified frequencies to itsCUe (along with a radar detected message). As shown in FIG. 2D, the CUemay implement a part of the interference detection management logic by(i) selecting the second frequency Y from the list of identifiedfrequencies, and (ii) transmitting a radar detection message to the AMFe(including an indication of frequencies X and Y).

In one variant, the AMFe transmits an acknowledgement signal to the CUe,identifies idle UEs being serviced by the DUe (or the broader gNB) usingfrequency X (step 206 in method 200), and transmits a paging request forthe identified UEs (step 208). In the embodiment of FIG. 2D, in responseto the paging request, the CUe uses the DUe to transition the identifiedUEs from idle/inactive to active/connected state and then instruct theUEs to switch from frequency X to frequency Y.

Access Node Initiated Redirect

Referring now to FIG. 3 , one embodiment of a method 300 of using a gNBredirect one or more UEs to a different frequency, without involving anetwork entity such as the AMF, is shown and described.

In steps 302-304 of FIG. 3 , upon detection of interference/radar in oneof the frequencies (e.g., frequency “X”, such as UNII-2 and UNII-2ebands in the 5 GHz unlicensed spectrum) where the access node (e.g., thegNB) is currently operating, the gNB picks a frequency where no radaroperations/interference are present (e.g., frequency “Y”), and preparesa redirect request (i.e., composes a new RRC CCCH payload RRCRedirect).

In step 306 of FIG. 3 , the gNB transmits/broadcasts the redirectrequest to the appropriate client/user devices (UEs). In one embodiment,a gNB transmits RRCRedirect in a PDCCH common search space (CSS) (forexample, Type0A or Type2 CSS) using a new DCI format scrambled with anew RNTI RD-RNTI that is predefined in the specification. The parametersof this PDCCH CSS are broadcast as part of PDCCH_ConfigCommon in systeminformation. The contents of the RRCRedirect message are similar tothose specified in the above embodiments, i.e., includes thecorresponding new frequency (“Y”) to which redirection of UEs is tooccur.

In step 308, idle user/client devices (RRC_IDLE UEs when not in idlemode DRX) read and decode the redirect request, e.g., read the DCI(downlink control information) and unscramble RD-RNTI to decodeRRCRedirect message.

In steps 310-312, for each value of CurrentOperatingFreq pair in theredirect (RRCRedirect) message, the UE compares it against the campedcell's ARFCN (absolute radio frequency channel number), and in step 312,if a match is found, the UE performs cell reselection to frequencyindicated in RedirectedOperatingFreq per TS 38.304.

FIG. 3A is a ladder diagram illustrating one approach for performing ofinterference detection (utilizing only an enhanced DU (DUe), asdiscussed below, to perform all the requisite management logic), inaccordance with one embodiment of the present disclosure. In theembodiment of FIG. 3A, a DUe performs radar detection, detects radarinterference at a first frequency X, selects a second frequency Y (e.g.,from a current or predetermined list of alternate frequencies) that isfree of radar operation, and instructs the user devices operating thatfrequency X to switch to frequency Y (e.g., using an RRCRedirectmessage). As described elsewhere in the disclosure, the user devices(UEs) in the system of FIG. 3A are able to receive the frequencyredirect message even if they are in idle/inactive modes. For example,the UEs periodically monitor a special redirect channel for the redirectmessage. In one embodiment, only idle/inactive UEs periodically monitorthe redirect channel, and the DUe may transmit/broadcast redirectmessages using both the redirect channel (in order to reach the idleUEs) and the current operating frequency X (to reach regular, activeUEs).

In another embodiment, all UEs connected to the DUe (regardless ofactivity or other status) monitor the redirect channel and the DUebroadcasts the redirect message using only the redirect channel.

One a UE has transitioned to the new frequency Y and transmitted a“redirect complete” message to the DUe, the DUe notifies the CUe thatthe UE has switched from X to Y. In the embodiment of FIG. 3A, theinterference detection and management is handled entirely by the DUe,and the CUe is merely kept up to date.

FIG. 3B is a ladder diagram illustrating another approach for performingof interference detection (utilizing an enhanced CU (CUe) and DU (DUe),as discussed below, to perform all the requisite management logic), inaccordance with another embodiment of the present disclosure. In theembodiment of FIG. 3B, the CUe instructs (e.g., periodically) the DUe toperform a radar detection operation. The DUe performs radar detection,detects radar operation on frequency X, and generates a list ofalternate frequencies that may be used by the DUe. In one embodiment,the DUe notifies the CUe of the radar operation detected on frequency Xand provides the list of alternate frequencies. The CUe selects thesecond frequency Y from the alternate frequencies and instructs theappropriate UEs (via the DUe) to switch from the first frequency X tothe second frequency Y.

FIG. 3C is a ladder diagram illustrating yet another approach forperforming of interference detection (utilizing an enhanced non-3GPPaccess node for performing all the requisite management logic), inaccordance with another embodiment of the present disclosure. In oneapproach, the non-3GPP access node may be a Wi-Fi AP (access point)operating in the unlicensed frequency spectrum used by Wi-Fi systems.The wireless access node of FIG. 3C performs all the requisiteinterference detection management logic including (i) performinginterference detection, (ii) detecting interference on a first frequencyX, (iii) identify alternate frequencies (e.g., other frequencies withinthe unlicensed frequency spectrum that are free of interference), (iv)select a second frequency Y that is free of interference, and (v)instruct the client device currently using frequency X to switch tofrequency Y.

Distributed gNB Architectures

Referring now to FIGS. 4A and 4B, an exemplary embodiment of thedistributed (CU/DU) gNB architecture according to the present disclosureis described.

As a brief aside, and referring to FIG. 4A, the CU 404 (also known asgNB-CU) is a logical node within the NR architecture 400 thatcommunicates with the NG Core 403, and includes gNB functions such astransfer of user data, session management, mobility control, RANsharing, and positioning; however, other functions are allocatedexclusively to the DU(s) 406 (also known as gNB-DUs) per various “split”options described subsequently herein in greater detail. The CU 404communicates user data and controls the operation of the DU(s) 406, viacorresponding front-haul (Fs) user plane and control plane interfaces408, 410.

Accordingly, to implement the Fs interfaces 408, 410, the (standardized)F1 interface is employed. It provides a mechanism for interconnecting agNB-CU 404 and a gNB-DU 406 of a gNB 402 within an NG-RAN, or forinterconnecting a gNB-CU and a gNB-DU of an en-gNB within an E-UTRAN.The F1 Application Protocol (F1AP) supports the functions of F1interface by signaling procedures defined in 3GPP TS 38.473. F1APconsists of so-called “elementary procedures” (EPs). An EP is a unit ofinteraction between gNB-CU and gNB-DU. These EPs are defined separatelyand are intended to be used to build up complete messaging sequences ina flexible manner. Generally, unless otherwise stated by therestrictions, the EPs may be invoked independently of each other asstandalone procedures, which can be active in parallel.

With the foregoing as a backdrop, a first architecture 420 configuredfor interference detection and management according to the presentdisclosure is shown in FIG. 4A. This architecture 420 includes a gNB 422having an enhanced CU (CUe) 424 and a plurality of enhanced DUs (DUe)426. It will be noted that some DU within a given gNB (see DU 406 asshown in FIG. 4A) may not be enhanced with the detection/managementcapabilities as described herein, or all may. Likewise, as referenced insome of the foregoing ladder diagrams, the detection/managementfunctionality may be split between the DUe and CUe of a given enhancedgNB 422, such as where the radar detection is performed by the DUe, andthe signaling and other protocols involved in UE frequency migration arehandled by the CUe (via the DUe).

As described in greater detail subsequently herein, these enhancedentities are enabled to permit efficient inter-process signaling andinterferer detection and management, whether autonomously or undercontrol of another logical entity (such as the NG Core 423/5G RAN withwhich the gNB communicates including an AMF (not shown), or componentsthereof).

The individual DUe's 426 in FIG. 4B communicate data and messaging withthe CUe 424 via interposed physical communication interfaces 428 andlogical interfaces 430. As previously described, such interfaces mayinclude a user plane and control plane, and be embodied in prescribedprotocols such as F1AP. In the illustrated embodiment, one CUe 424 isassociated with one or more DUe's 426, yet a given DUe is onlyassociated with a single CUe. Likewise, the single CUe 424 may becommunicative with a single NG Core 423, such as that operated by an MNOor MSO, or multiple cores. Each NG Core 423 may have multiple gNBs 402associated therewith as well.

Also shown are individual detection management logic (DML) modules 421for each of the “enhanced” entities (CUe/DUe). These logic modules maybe heterogeneous or homogenous in nature, and may overlap infunctionality if desired (e.g., each may perform a similar function tothe other, or alternatively have only complementary function sets). Inone variant, a client-server model is utilized wherein the CUe DML actsas a server to the DUe DML clients within a given gNB 422. Moreover,while several DMLs 421 are shown, the requisite functionality requiredby the methods described herein may in some scenarios by supportedentirely by one DML 421 alone (e.g., located in the DUe 426 or the CUe424).

It will also be appreciated that while described primarily with respectto a unitary gNB-CU entity or device 422 as shown in FIG. 4B, thepresent disclosure is in no way limited to such architectures. Forexample, the techniques described herein may be implemented as part of adistributed or dis-aggregated or distributed CU entity (e.g., onewherein the user plane and control plane functions of the CU aredis-aggregated or distributed across two or more entities such as a CU-C(control) and CU-U (user)), and/or other functional divisions areemployed.

It is also noted that heterogeneous architectures of eNBs or femtocells(i.e., E-UTRAN LTE/LTE-A Node B's or base stations) and gNBs may beutilized consistent with the architecture of FIG. 4B. For instance, agiven DUe may act (i) solely as a DUe (i.e., 5G NR PHY node) and operateoutside of an E-UTRAN macrocell, or (ii) be physically co-located withan eNB or femtocell and provide NR coverage within a portion of the eNBmacrocell coverage area, or (iii) be physically non-colocated with theeNB or femtocell, but still provide NR coverage within the macrocellcoverage area.

In the 5G NR model, the DU(s) comprise logical nodes that each mayinclude varying subsets of the gNB functions, depending on thefunctional split option. DU operation is controlled by the CU (andultimately for some functions by the NG Core). Accordingly, splitoptions between the DUe 426 and CUe 424 in the present disclosure mayinclude for example:

-   -   Option 1 (RRC/PCDP split)    -   Option 2 (PDCP/RLC split)    -   Option 3 (Intra RLC split)    -   Option 4 (RLC-MAC split)    -   Option 5 (Intra MAC split)    -   Option 6 (MAC-PHY split)    -   Option 7 (Intra PHY split)    -   Option 8 (PHY-RF split)

Under Option 1 (RRC/PDCP split), the RRC (radio resource control) is inthe CUe 424 while PDCP (packet data convergence protocol), RLC (radiolink control), MAC, physical layer (PHY) and RF are kept in the DUe's426, thereby maintaining the entire user plane in the distributed unit.

Under Option 2 (PDCP/RLC split), there are two possible variants: (i)RRC, PDCP maintained in the CUe 424, while RLC, MAC, physical layer andRF are in the DUe's 426; and (ii) RRC, PDCP in the CUe 424 (with splituser plane and control plane stacks), and RLC, MAC, physical layer andRF in the DUe's 426.

Under Option 3 (Intra RLC Split), two splits are possible: (i) splitbased on automatic repeat request (ARQ) protocols; and (ii) split basedon TX RLC and RX RLC.

Under Option 4 (RLC-MAC split), RRC, PDCP, and RLC are maintained in theCUe 424, while MAC, physical layer, and RF are maintained in the DUe's426.

Under Option 5 (Intra-MAC split), RF, physical layer and lower part ofthe MAC layer (Low-MAC) are in the DUe's 426, while the higher part ofthe MAC layer (High-MAC), RLC and PDCP are in the CUe 424.

Under Option 6 (MAC-PHY split), the MAC and upper layers are in the CUe424, while the PHY layer and RF are in the DUe's 426. The interfacebetween the CUe 424 and DUe's 426 carries data, configuration, andscheduling-related information (e.g. Modulation and Coding Scheme orMCS, layer mapping, beamforming and antenna configuration, radio andresource block allocation, etc.) as well as measurements.

Under Option 7 (Intra-PHY split), different sub-options for UL (uplink)and DL downlink) may occur independently. For example, in the UL, FFT(Fast Fourier Transform) and CP removal may reside in the DUe's 426,while remaining functions reside in the CUe 424. In the DL, FFT and CPaddition may reside in the DUe 426, while the remainder of the PHYresides in the CUe 424.

Finally, under Option 8 (PHY-RF split), the RF and the PHY layer may beseparated to, inter alia, permit the centralization of processes at allprotocol layer levels, resulting in a high degree of coordination of theRAN. This allows optimized support of functions such as CoMP, MIMO, loadbalancing, and mobility.

The foregoing split options are intended to enable flexible hardwareimplementations which allow scalable cost-effective solutions, as wellas coordination for e.g., performance features, load management, andreal-time performance optimization. Moreover, configurable functionalsplits enable dynamic adaptation to various use cases and operationalscenarios, including the interference detection and management scenariosdescribed herein. Factors considered in determining how/when toimplement such options can include: (i) QoS requirements for offeredservices (e.g. low latency, high throughput); (ii) support ofrequirements for user density and load demand per given geographicalarea (which may affect RAN coordination); (iii) availability oftransport and backhaul networks with different performance levels; (iv)application type (e.g. real-time or non-real time); (v) featurerequirements at the Radio Network level (e.g. Carrier Aggregation). Inone such example, if a backhaul (e.g., that used in an MSO or MNOnetwork for backhauling a premises or site to the core or otherfacility) operates on an unlicensed channel subject to DFS requirement,then the interferer/radar detection becomes a more urgent and importanttask, since disruption of the backhaul channel(s) could have significantconsequences for many users of the equipment being backhauled. As such,the Options/splits selected for the various gNBs can be based on suchurgency and reliability (e.g., to reduce disruption and latency to themaximum degree, and/or increase reliability to the maximum degree).

DUe Apparatus

FIG. 5 illustrates an exemplary configuration of an enhanced distributedunit (DUe) 426 according to the present disclosure. As shown, the DUe426 includes, inter alia, a processor apparatus or subsystem 502, aprogram memory module 504, mass storage 505, DML function logic 506, oneor more network interfaces 508, and one or more RF (e.g., 5G/New Radio)PHY interfaces 509.

In the exemplary embodiment, the processor 502 may include one or moreof a digital signal processor, microprocessor, field-programmable gatearray, GPU, or plurality of processing components mounted on one or moresubstrates. The processor 502 may also comprise an internal cachememory, and is in communication with a memory subsystem 504, which cancomprise, e.g., SRAM, flash and/or SDRAM components. The memorysubsystem may implement one or more of DMA type hardware, so as tofacilitate data accesses as is well known in the art. The memorysubsystem of the exemplary embodiment contains computer-executableinstructions which are executable by the processor 502.

The RF interface 509 is configured to comply with the relevant PHYstandards which it supports (e.g., 5G NR RAN, E-UTRAN, WLAN such as802.11-16, and/or others as applicable) in the area/premises/venue beingserved. The antenna(s) 510 of the DUe NR radio may include multiplespatially diverse individual elements in e.g., a MIMO- or MISO-typeconfiguration, such that spatial diversity of the received signals canbe utilized. Moreover, a phased array or similar arrangement can be usedfor spatial resolution within the environment, such as based on timedelays associated with signals received by respective elements.

The processing apparatus 502 is configured to execute at least onecomputer program stored in memory 504 (e.g., a non-transitory computerreadable storage medium); in the illustrated embodiment, such programsinclude DUe detection and management controller logic (DML) 506, such aswhether detection of an interfering radar has occurred or not, receiptand decode of the enhanced IEs, and other logical functions performed bythe DUe 426 as described elsewhere herein. Other embodiments mayimplement such functionality within dedicated hardware, logic, and/orspecialized co-processors (not shown). The DUe controller logic 506 is afirmware or software module that, inter alia, communicates with acorresponding CUe detection logic portion (i.e., for detection andmessage exchange and protocol implementation), and/or other upstream orbackend entities such as those within the NG Core 403 in alternateembodiments.

In some embodiments, the DUe DML logic 506 utilizes memory 504 or otherstorage 505 configured to temporarily hold a number of data relating tothe various IE's (including those in Tables 2-5 described previouslyherein) before transmission via the network interface(s) 508 to the CUe424 or NG Core 423 (or AMF). In other embodiments, application programinterfaces (APIs) such as those included in an MSO-provided applicationor those natively available on the DUe 426 may also reside in theinternal cache or other memory 504. Such APIs may include common networkprotocols or programming languages configured to enable communicationwith the DUe 426 and other network entities (e.g., via API “calls” tothe DUe by MSO network processes tasked with gathering interferer, load,configuration, or other data). Application program interfaces (APIs) maybe included in an MSO-provided applications, or installed with otherproprietary software or firmware that comes prepackaged with theDUe/CUe.

It will be appreciated that any number of physical configurations of theDUe 426 may be implemented consistent with the present disclosure. Asnoted above, the functional “split” between DUe's 426 and CUe 424 hasmany options, including those which may be invoked dynamically (e.g.,where the functionality may reside in both one or more DUe's 426 and thecorresponding CUe 424, but is only used in one or the other at a timebased on e.g., operational conditions such as predicated on detectedinterferers which invoke new “split” logic to further optimize operationof the network, such as to result in the least interruption of servicefor e.g., MSO subscribers operating in the NR-U bands of interest).

CUe Apparatus

FIG. 6 illustrates a block diagram of an exemplary embodiment of a CUe424 apparatus, useful for operation in accordance with the presentdisclosure.

In one exemplary embodiment as shown, the CUe 424 includes, inter alia,a processor apparatus or subsystem 602, a program memory module 604, CUeDML controller logic 606 (here implemented as software or firmwareoperative to execute on the processor 602), network interfaces 610 forcommunications and control data communication with the relevant DUe's426, and a communication with the NG Core 423 (and AMF of the cognizantRAN), as well as with other gNBs via the Xn interfaces 426, 428.

In one exemplary embodiment, the CUe's 424 are maintained by the MSO andare each configured to utilize a non-public IP address within anIMS/Private Management Network “DMZ” of the MSO network. As a briefaside, so-called DMZs (demilitarized zones) within a network arephysical or logical sub-networks that separate an internal LAN, WAN,PAN, or other such network from other untrusted networks, usually theInternet. External-facing servers, resources and services are disposedwithin the DMZ so they are accessible from the Internet, but the rest ofthe internal MSO infrastructure remains unreachable or partitioned. Thisprovides an additional layer of security to the internal infrastructure,as it restricts the ability of surreptitious entities or processes todirectly access internal MSO servers and data via the untrusted network,such as via a CUe “spoof” or MITM attack whereby an attacker mightattempt to hijack one or more CUe to obtain data from the correspondingDUe's (or even UE's utilizing the DUe's).

Although the exemplary CUe 424 may be used as described within thepresent disclosure, those of ordinary skill in the related arts willreadily appreciate, given the present disclosure, that the “centralized”controller unit 424 may in fact be virtualized and/or distributed withinother network or service domain entities (e.g., within one of the Due426 of a given gNB 422, within the NG Core 423 or an MSO entity such asa server, a co-located eNB, etc.), and hence the foregoing apparatus 424of FIG. 6 is purely illustrative.

In one embodiment, the processor apparatus 602 may include one or moreof a digital signal processor, microprocessor, field-programmable gatearray, GPU or plurality of processing components mounted on one or moresubstrates. The processor apparatus 602 may also comprise an internalcache memory. The processing subsystem is in communication with aprogram memory module or subsystem 604, where the latter may includememory which may comprise, e.g., SRAM, flash and/or SDRAM components.The memory module 604 may implement one or more of direct memory access(DMA) type hardware, so as to facilitate data accesses as is well knownin the art. The memory module of the exemplary embodiment contains oneor more computer-executable instructions that are executable by theprocessor apparatus 602. A mass storage device (e.g., HDD or SSD, oreven NAND flash or the like) is also provided as shown.

The processor apparatus 602 is configured to execute at least onecomputer program stored in memory 604 (e.g., the logic of the CUeincluding enhanced detection and management and associated IEfunctionality in the form of software or firmware that implements thevarious functions described herein). Other embodiments may implementsuch functionality within dedicated hardware, logic, and/or specializedco-processors (not shown).

In one embodiment, the CUe 424 is further configured to register knowndownstream devices (e.g., access nodes including DUe's 426, other CUedevices), and centrally control the broader gNB functions (and anyconstituent peer-to-peer sub-networks or meshes). Such configurationinclude, e.g., providing network identification (e.g., to DUe's, gNBs,client devices such as roaming MNO UEs, and other devices, or toupstream devices such as MNO or MSO NG Core portions 423 and theirentities, including the AMF for the RAN to which the gNB belongs), andmanaging capabilities supported by the gNB's NR RAN.

The CUe 424 may further be configured to directly or indirectlycommunicate with one or more authentication, authorization, andaccounting (AAA) servers of the network, such as via the interface 608shown in FIG. 6 . The AAA servers, whether locally maintained by the MSOor remotely by e.g., an MNO of the subscriber, are configured to provideservices for, e.g., authorization and/or control of network subscribers(including roaming MNO “visitors”) for controlling access and enforcingpolicies, auditing usage, and providing the information necessary tobill for services.

AMFe Apparatus

FIG. 7 illustrates an exemplary configuration of an enhanced AMF (AMFe)701 according to the present disclosure. As shown, the AMFe 701includes, inter alia, a processor apparatus or subsystem 702, a programmemory module 704, mass storage 705, AMF DML function logic 706, and oneor more network interfaces 708 so as to support the 3GPP N1 and N2interface functions.

In the exemplary embodiment, the processor 702 may include one or moreof a digital signal processor, microprocessor, field-programmable gatearray, GPU, or plurality of processing components mounted on one or moresubstrates. The processor 502 may also comprise an internal cachememory, and is in communication with a memory subsystem 504, which cancomprise, e.g., SRAM, flash and/or SDRAM components. The memorysubsystem may implement one or more of DMA type hardware, so as tofacilitate data accesses as is well known in the art. The memorysubsystem of the exemplary embodiment contains computer-executableinstructions which are executable by the processor 502.

The processing apparatus 702 is configured to execute at least onecomputer program stored in memory 704 (e.g., a non-transitory computerreadable storage medium); in the illustrated embodiment, such programsinclude AMFe detection and management controller logic (DML) 706, suchas whether detection of an interfering radar has occurred or not,receipt and decode of the enhanced IEs, and other logical functionsperformed by the AMFe 701 as described elsewhere herein (when utilizedwithin the architecture). Other embodiments may implement suchfunctionality within dedicated hardware, logic, and/or specializedco-processors (not shown). The AMFe controller logic 706 is a firmwareor software module that, inter alia, communicates with a correspondingCUe detection logic portion (i.e., for detection and message exchangeand protocol implementation), and/or other upstream or backend entitiessuch as those further within the NG Core (see FIG. 8 ) as well aslogical connections with UE.

In some embodiments, the DML logic 706 utilizes memory 704 or otherstorage 705 configured to temporarily hold a number of data relating tothe various IE's (including those in Tables 2-5 described previouslyherein) before transmission via the network interface(s) to the CUe 424or NG Core 423. In other embodiments, application program interfaces(APIs) may also reside in the internal cache or other memory 704. SuchAPIs may include common network protocols or programming languagesconfigured to enable communication with the AMFe 701 and other networkentities (e.g., via API “calls” to the AMFe by MSO network processestasked with gathering interferer, load, configuration, or other data).Application program interfaces (APIs) may be included in an MSO-providedapplications or installed with other proprietary software or firmwarethat comes prepackaged with the AMF hardware.

UEe Apparatus

FIG. 8 illustrates a block diagram of an exemplary embodiment of anenhanced UE (UEe) apparatus 433, useful for operation in accordance withthe present disclosure.

In one exemplary embodiment as shown, the UEe 433 includes, inter alia,a processor apparatus or subsystem 811, a program memory module 807, UEDML logic 803 (here implemented as software or firmware operative toexecute on the processor 811), and wireless interface 813 forcommunications with the relevant RANs (e.g., 5G-NR/NR-U RAN), a userinterface (UI) 817 such as a capacitive touchscreen device, and a WLANfront end/radio and associated baseband 833. The RF interfaces 813, 833are each configured to comply with the relevant PHY standards which itsupports (e.g., 3GPP Rel. 15/16/17 or IEEE Std. 802.11). The antenna(s)819 of the UEe radios may include multiple spatially diverse individualelements in e.g., a MIMO- or MISO-type configuration, such that spatialdiversity of the received signals can be utilized. Moreover, a phasedarray or similar arrangement can be used for spatial resolution withinthe environment, such as based on time delays associated with signalsreceived by respective elements.

In one embodiment, the processor apparatus 811 may include one or moreof a digital signal processor, microprocessor, field-programmable gatearray, or plurality of processing components mounted on one or moresubstrates. The processor apparatus 811 may also comprise an internalcache memory, and modem 815 (e.g., baseband/MAC chipset). As indicated,the UEe includes a DML module 803 in the program memory which is incommunication with the processing subsystem, where the former mayinclude memory which may comprise, e.g., SRAM, flash and/or SDRAMcomponents. The memory module 807 may implement one or more of directmemory access (DMA) type hardware, so as to facilitate data accesses asis well known in the art. The memory module of the exemplary embodimentcontains one or more computer-executable instructions that areexecutable by the processor apparatus 811. A mass storage device (e.g.,HDD or SSD, or NAND/NOR flash or the like, such as via eMCC) is alsoprovided as shown.

Other embodiments may implement the DML functionality within dedicatedhardware, logic, and/or specialized co-processors (not shown).

As noted, the UEe 433 may include a DML module 803 which is configuredto, inter alia, (i) enable receipt of network-initiated paging messagesand associated data relating to interferer (e.g., weather radar)detection; and (ii) redirect or migration messages and associated datacausing the UEe 433 to move to one or more new unencumbered carriers.Moreover, in one variant, the DML logic 803 may also be configured to(iii) aid in detection of the interferer, such as by utilizing its RFfront end/antennae to make environmental measurements within one or moreprescribed bands, including ones which it may presently be operating in,and pass this data to the gNB (and AMF, depending on configuration). Assuch, the DML logic is in communication with the modem 815 (via itsexecution on the processor) regarding detection of interferers inunlicensed spectrum, and for utilizing of the aforementioned paging andredirection data when received from the gNB. The modem 815 processes thebaseband control and data signals relating to these functions fortransmission or reception as applicable via the RF frond end module 803.

In some embodiments, the UEe 433 also utilizes memory 807 or otherstorage 821 configured to temporarily hold a number of data relating tothe various gNB associations, interfered-with or encumbered carriers,detection data (when so equipped), and other relevant data which may bereceived via the aforementioned IEs.

In other embodiments, application program interfaces (APIs) such asthose included in an MSO-provided application or those nativelyavailable on the UEe may also reside in the internal cache or othermemory 807. Such APIs may include common network protocols orprogramming languages configured to enable communication with the UEe433 and other network entities (e.g., via API “calls” to the UEe by MSOnetwork processes tasked with NR-U interference detection and carriermanagement).

As an aside, a downloadable application or “app” may be available tosubscribers of an MSO or cable network (and/or the general public,including MSO “partner” MNO subscribers), where the app allows users toconfigure their UEe via the UI to implement enhanced functionality,including data collection and reporting back to the MSO core network soas to enable, inter alia, NR-U carrier interference when roaming,congestion, or other attributes which may be useful in implementinge.g., the methodologies of FIGS. 2 and 3 discussed above. Applicationprogram interfaces (APIs) may be included in MSO-provided applications,installed with other proprietary software that comes prepackaged withthe UEe. Alternatively, the relevant MNO may provide its subscriberswith the aforementioned functionality (e.g., as a pre-loaded app on theUEe at distribution, or later via download), or as a firmware update tothe UEe stack conducted OTA.

FIG. 9 shows one embodiment of an architecture 900 for interworkingbetween the enhanced 5GS (including AMFe, enhanced gNB 422, and enhancedUE (UEe) 433 if used), and an EPC/E-UTRAN. Two different RANtechnologies are supported; i.e., E-UTRAN (4G/4.5G) 902, and 5G (NG-RAN)904, with the 5G network 904 also enabled for radar or other interfererdetection and management.

Additional Embodiments

System Information Changes—

System information (SI) broadcast by a gNB can also be enhanced for thepurposes of DFS. For example, System Information Block 1 (SIB1) inRel-16 NR currently conveys uac-BarringInfo that contains cell accesscontrol parameters for different UE access categories. The UAC barringinformation may be enhanced with frequency redirection information suchthat IDLE/INACTIVE/CONNECTED UEs can obtain this information fromreading SI, where the SI update is indicated via paging.

Solutions for RRC_INACTIVE UEs—

It will be recognized that the exemplary solutions for RRC_IDLE UEs canin one approach be reused for RRC_INACTIVE UEs. RRC_INACTIVE UEs may inone variant be configured to, after completing cell change to the newfrequency, transmit a RAN-based Notification Area Update message thatconfirms the completion of the redirect procedure due to DFS.

Solutions for RRC_CONNECTED UEs—

In addition to using existing handover mechanisms for RRC_CONNECTED UEs,a new DFS event detection message is utilized in one variant of thepresent disclosure for, inter alia, UEs to provide assistance to the gNBwith DFS. Consider the exemplary scenario of multi-radio UEs that areequipped with both Wi-Fi and 3GPP cellular radios. As previouslydescribed, IEEE Std. 802.11 technologies incorporate transmission andreception of channel switch announcement (CSA) frames in the event ofradar detection. In one implementation of the present disclosure, a UEthat detects such a message via its Wi-Fi radio (or yet other airinterface) can report this to the NR-U gNB using an RRC messageconfigured for such purposes. Note that in 3GPP Rel-15, measurement ofIEEE WLAN RSSI based on Wi-Fi beacons is defined for UEs in any RRCstate state [16], while in Rel-16, ATSSS WLAN channel utilization andbeacon RSSI measurement reports have been proposed. Hence, in onevariant, the RRC message referenced above is an RRC message carried onDCCH from a UE to the network. Other solutions will be appreciated bythose of ordinary skill given the present disclosure.

It will also be appreciated that while there are existing handovermechanisms for RRC_CONNECTED UEs, it may be the case that the number ofUEs in RRC_CONNECTED are too numerous, and utilizing such extanthandover mechanism for all the UEs may require use of too many slots.Alternatively, due to limitations on channel access (e.g.listen-before-talk) and the maximum duration of transmission during agiven channel access, a gNB may have to perform a channel accessprocedure multiple times, in which case there would be additional delaydue to such repetition of the channel access procedure. In such cases,the gNB may, via its DML, logic, use a more fitting method such asannouncing the channel redirection via system information, e.g. SystemInformation Block 1 (SIB1), updating uac-BarringInfo and providingfrequency redirection information.

Solutions for Indication to other gNBs—

Thus far, the present disclosure has in some aspects focused on how toindicate frequency changes resulting from or related to DFS to UEs.Notably, there are several instances where one or more gNBs may berelying on the downlink transmissions of a particular gNB for variouspurposes. It is beneficial in certain cases for the relied-upon gNB(s)to indicate to these relying gNBs that it has to change its operatingfrequency due to DFS, so that the relying gNBs can stop monitoringnon-existent gNB transmissions. Several example instances of theforegoing include:

-   -   Radio interface-based synchronization (RIBS) that has been        defined for LTE and is under discussion for NR as part of        Rel-17. Here, downstream gNBs rely on reference signal        transmissions from upstream gNBs to acquire time synchronization        to a master clock.    -   Integrated access and backhaul (IAB), wherein a NR child node        (gNB) relies on a donor or parent node (gNB) for its wireless        backhaul link.    -   Remote interference management (RIM) in Rel-16 NR where a victim        gNB listens to reference signal transmissions from an aggressor        gNB to determine if RIM still persists.

For the case of IAB, in one embodiment, the SSB transmitted by the IABdonor to the IAB child nodes includes a modified PBCH payload or otherelement to indicate that the parent gNB is about to cease transmission.

For the case of RIM and RIBS, in one embodiment a reserved RIM-RS orRIBS-RS is transmitted to indicate to downstream gNBs that the upstreamgNB is about to cease transmissions. For example, the sequence index ofthe reserved RIM-RS or RIBS-RS can be mapped to such an indication inthe 3GPP specification.

Other solutions for the foregoing IAB, RIM and RIBS scenarios will beappreciated by those of ordinary skill given the present disclosure.

It will be recognized that while certain aspects of the disclosure aredescribed in terms of a specific sequence of steps of a method, thesedescriptions are only illustrative of the broader methods of thedisclosure, and may be modified as required by the particularapplication. Certain steps may be rendered unnecessary or optional undercertain circumstances. Additionally, certain steps or functionality maybe added to the disclosed embodiments, or the order of performance oftwo or more steps permuted. All such variations are considered to beencompassed within the disclosure disclosed and claimed herein.

While the above detailed description has shown, described, and pointedout novel features of the disclosure as applied to various embodiments,it will be understood that various omissions, substitutions, and changesin the form and details of the device or process illustrated may be madeby those skilled in the art without departing from the disclosure. Thisdescription is in no way meant to be limiting, but rather should betaken as illustrative of the general principles of the disclosure. Thescope of the disclosure should be determined with reference to theclaims.

It will be further appreciated that while certain steps and aspects ofthe various methods and apparatus described herein may be performed by ahuman being, the disclosed aspects and individual methods and apparatusare generally computerized/computer-implemented. Computerized apparatusand methods are necessary to fully implement these aspects for anynumber of reasons including, without limitation, commercial viability,practicality, and even feasibility (i.e., certain steps/processes simplycannot be performed by a human being in any viable fashion).

What is claimed is:
 1. A computerized method of managing detection ofinterference in a first frequency band being used in a wireless accessnetwork by a wireless access node and one or more wireless user devicesconnected to the wireless access network through the wireless accessnode, the computerized method comprising: detecting wirelessinterference associated with the first frequency band; based on thedetecting, selecting at least one second frequency band which at leastmeets one or more interference-related criteria; determining that theone or more wireless user devices are initially in at least one of (i)an idle mode or (ii) an inactive mode; sending a first signal to the oneor more wireless user devices to cause the one or more wireless userdevices to transition from the at least one of (i) the idle mode or (ii)the inactive mode to at least one of (i) a connected mode or (ii) anactive mode, wherein the first signal and the transition to the at leastone of (i) the connected mode or (ii) the active mode comprises a FifthGeneration (5G) Third Generation Partnership Project (3GPP) compliantpaging procedure, and the first signal is initiated by an access andmobility management function (AMF); and sending a second signal to theone or more wireless user devices to cause the one or more wireless userdevices to switch from use of the first frequency band to use of the atleast one second frequency band, wherein the sending of the secondsignal to the one or more wireless user devices to cause the switchingto the use of the at least one second frequency band comprises using a5G 3GPP compliant frequency change procedure.
 2. The computerized methodof claim 1, wherein the switching to the use of the at least one secondfrequency band comprises switching to use of two or more sub-bands.
 3. Acomputerized method of managing detection of interference in a firstfrequency band being used in a wireless access network by a wirelessaccess node and one or more wireless user devices connected to thewireless access network through the wireless access node, thecomputerized method comprising: detecting wireless interferenceassociated with the first frequency band; based on the detecting,selecting at least one second frequency band which at least meets one ormore interference-related criteria; determining that the one or morewireless user devices are initially in at least one of (i) an idle modeor (ii) an inactive mode; causing the wireless access node to send datarepresentative of a redirect message to the one or more wireless userdevices without first causing the one or more wireless user devices totransition from the at least one of (i) the idle mode or (ii) theinactive mode to at least one of (i) a connected mode or (ii) an activemode; and cause the one or more wireless user devices to switch from useof the first frequency band to use of the at least one second frequencyband.
 4. The computerized method of claim 3, wherein the causing of thewireless access node to send the data representative of the redirectmessage to the one or more wireless user devices comprises causing thewireless access node to send data configured to signal the one or morewireless user devices to switch their connection to the wireless accessnetwork from the first frequency band to the at least one secondfrequency band.
 5. The computerized method of claim 3, furthercomprising causing the one or more wireless user devices to monitor aphysical redirect channel for the data representative of the redirectmessage.
 6. The computerized method of claim 5, wherein the causing theone or more wireless user devices to monitor the physical redirectchannel for the data representative of the redirect message comprisescausing the one or more wireless user devices to monitor the physicalredirect channel for the data representative of the redirect messagewhile in the at least one of (i) the idle mode or (ii) the inactivemode.
 7. The computerized method of claim 5, wherein the causing the oneor more wireless user devices to monitor the physical redirect channelfor the data representative of the redirect message comprises causingthe one or more wireless user devices to monitor the physical redirectchannel for the data representative of the redirect message periodicallyat a predetermined monitoring frequency, the predetermined monitoringfrequency based at least on a frequency of monitoring of a pagingchannel.
 8. The computerized method of claim 5, wherein the causing theone or more wireless user devices to monitor the physical redirectchannel for the data representative of the redirect message comprisescausing the one or more wireless user devices to monitor the physicalredirect channel for the data representative of the redirect messageperiodically at a predetermined monitoring frequency, wherein thepredetermined monitoring frequency is based at least on historicalinterference data.
 9. The computerized method of claim 8, furthercomprising obtaining the historical interference data, the historicalinterference data comprising a number of times that interference isdetected in the first frequency band within a time period.
 10. Awireless network access node configured to provide wireless networkaccess to one or more wireless user devices within a wireless accessnetwork via use of unlicensed frequency spectrum, the wireless networkaccess node comprising: a digital processor apparatus; a wirelessnetwork interface in data communication with the digital processorapparatus; and a computer readable storage medium in data communicationwith the digital processor apparatus, the computer readable storagemedium comprising at least one computer program configured to, whenexecuted on the digital processor apparatus, cause the wireless networkaccess node to: perform interference detection for at least one firstfrequency; based on the interference detection, select at least onesecond frequency; and cause redirect of the one or more wireless userdevices from use of the at least one first frequency to use of the atleast one second frequency; wherein: the one or more wireless userdevices are initially in at least one of an idle or inactive state; theat least one first frequency and the at least one second frequency arein the unlicensed frequency spectrum; the unlicensed frequency spectrumis part of a Fifth Generation (5G) Third Generation Partnership Project(3GPP) New Radio-Unlicensed (NR-U) spectrum; and the wireless accessnetwork is at least in part working in NR-U standalone deployment.
 11. Awireless network access node configured to provide wireless networkaccess to one or more wireless user devices within a wireless accessnetwork via use of unlicensed frequency spectrum, the wireless networkaccess node comprising: a digital processor apparatus; a wirelessnetwork interface in data communication with the digital processorapparatus; and a computer readable storage medium in data communicationwith the digital processor apparatus, the computer readable storagemedium comprising at least one computer program configured to, whenexecuted on the digital processor apparatus, cause the wireless networkaccess node to: perform interference detection for at least one firstfrequency; based on the interference detection, select at least onesecond frequency; and cause redirect of the one or more wireless userdevices from use of the at least one first frequency to use of the atleast one second frequency; wherein: the one or more wireless userdevices are initially in at least one of an idle or inactive state; theat least one first frequency and the at least one second frequency arein the unlicensed frequency spectrum; and the wireless network accessnode comprises a Third Generation Partnership Project (3GPP) New Radio(NR) gNB comprising at least one of (i) an enhanced central unit (CUe)or (ii) at least one enhanced distributed unit (DUe) in datacommunication with the CUe.
 12. The wireless network access node ofclaim 11, wherein: the interference detection is performed by the atleast one DUe; and the selection of the at least one second frequency isperformed by the CUe.
 13. A wireless network access node configured toprovide wireless network access to one or more wireless user deviceswithin a wireless access network via use of unlicensed frequencyspectrum, the wireless network access node comprising: a digitalprocessor apparatus; a wireless network interface in data communicationwith the digital processor apparatus; and a non-transitory computerreadable storage medium in data communication with the digital processorapparatus, the non-transitory computer readable storage medium includingat least one computer program configured to, when executed on thedigital processor apparatus, cause the wireless network access node to:perform interference detection for at least one first frequency; senddata representative of a RAN (radio access network) configuration updateto an AMF (access and mobility management function) in a 5G Core (5GC),the data representative of a RAN configuration update comprising datarelated to the interference detection; based on the interferencedetection, select at least one second frequency; and cause redirect ofthe one or more wireless user devices from use of the at least one firstfrequency to use of the at least one second frequency; wherein: the oneor more wireless user devices are initially in at least one of an idleor inactive state; and the at least one first frequency and the at leastone second frequency are in the unlicensed frequency spectrum.
 14. Thewireless network access node of claim 13, where the selection of the atleast one second frequency comprises evaluating a plurality ofpre-selected frequency bands with respect to interference.
 15. Thewireless network access node of claim 14, wherein the plurality ofpre-selected frequency bands is based at least in part on historicalinterference data.
 16. A wireless network access node configured toprovide wireless network access to one or more wireless user deviceswithin a wireless access network via use of unlicensed frequencyspectrum, the wireless network access node comprising: a digitalprocessor apparatus; a wireless network interface in data communicationwith the digital processor apparatus; and a non-transitory computerreadable storage medium in data communication with the digital processorapparatus, the non-transitory computer readable storage medium includingat least one computer program configured to, when executed on thedigital processor apparatus, cause the wireless network access node to:perform interference detection for at least one first frequency; basedon the interference detection, select at least one second frequency, theselection of the at least one second frequency comprising (i) receipt ofa predetermined data structure of alternate frequencies and (ii)identification of an unoccupied frequency from the predetermined datastructure of the alternate frequencies; and cause redirect of the one ormore wireless user devices from use of the at least one first frequencyto use of the at least one second frequency; wherein: the one or morewireless user devices are initially in at least one of an idle orinactive state; and the at least one first frequency and the at leastone second frequency are in the unlicensed frequency spectrum.
 17. Thewireless network access node of claim 16, wherein: the wireless networkaccess node comprises a Wi-Fi access point (AP); and the unlicensedfrequency spectrum comprises a wireless spectrum used by Wi-Fi systems.18. The wireless network access node of claim 16, wherein the unlicensedfrequency spectrum comprises a New Radio-Unlicensed (NR-U) spectrum. 19.Computer readable apparatus comprising a non-transitory storage medium,the non-transitory storage medium comprising at least one computerprogram having a plurality of instructions, the plurality ofinstructions configured to, when executed on a processing apparatus,cause a wireless user device to: obtain first data representative ofdetection of channel interference, the detection comprising detection ofone or more radar signals in a frequency or frequency band being used bythe wireless user device; monitor a redirect channel for second datarepresentative of a redirect message, the monitoring of the redirectchannel for the second data representative of the redirect messagecomprising a monitoring of the redirect channel periodically at apredetermined monitoring frequency, the predetermined monitoringfrequency established via use of interference data relating to a timeperiod prior to a then-current time, the interference data enabling atleast one of (i) minimization of wireless user device power consumption,or (ii) discovery by the wireless user device of the second data withina certain time period; and based at least on the first data and thesecond data, perform a channel frequency redirect from the frequency orfrequency band to at least one other frequency or frequency band. 20.The computer readable apparatus of claim 19, wherein the monitoring ofthe redirect channel for the second data comprises monitoring theredirect channel while the wireless user device is in at least one of(i) an idle mode or (ii) an inactive mode.